The supplying of molten metal to a die casting machine and particularly the pouring of a preselected amount of molten metal into the cold chamber of a die casting machine has long been a problem in the die casting industry. The ladling of the molten metal from a bath, and then the transferring and pouring of the material into the die casting machine, has normally involved substantial manual manipulation so as to ensure that the molten metal is properly poured into the machine. However, this manual operation is obviously dangerous to the operating personnel in view of their exposure to the hot molten metal. This technique, which is necessarily relatively inefficient, also normally results in relatively inefficient use of material in that there is normally substantially spillage of molten metal. This manual operation also makes controlling the volume of molten metal which is to be supplied to the die casting machine extremely difficult, which in turn results in material wastage and/or improper die castings.
To overcome this problem, numerous attempts have been made at providing a machine which will automatically or substantially automatically transfer the molten metal from the bath to the die casting machine. However, to the best of my knowledge, all of these prior attempts have encountered various problems which have prevented a practical solution to this problem. For example, the prior devices have not permitted an efficient yet automatic transfer of this metal from the bath to the die casting machine without spillage and/or without requiring elaborate guide troughs and the like.
In one known apparatus, there is provided a swingable arm having a ladle mounted on the free end thereof, which ladle can be swingably moved from a position wherein it is immersed in a bath of molten metal to a position for pouring the metal into the cold chamber of a die casting machine. However, the ladle is fixed relative to the arm so that the ladle continuously tilts as the arm swings, whereupon pouring of metal from the ladle begins before the ladle is positioned over the cold chamber and continues over a substantial angular extent, thereby resulting in substantial spillage and hence wastage of the molten metal. This is obviously undesirable from both an economical and a safety standpoint.
To overcome these latter mentioned problems, a further apparatus is known wherein the ladle is interconnected to the swing arm by means of an intermediate linkage, such as a toggle arm, cams or the like. This linkage controls the tilting of the ladle only when the swing arm approaches the pouring position. However, this known apparatus is undesirable since this linkage substantially increases the mechanical complexity, weight and cost of the overall apparatus. This linkage has also been observed to seriously effect the mechanical dependability of the apparatus since the linkage normally involves a substantial number of hinge points which undergo rapid wear when utilized in this environment and when exposed to repetitive useage, which wear prevents free movement of the hinges and thus results in erratic pouring of the metal.
Thus, it is an object of the present invention to provide an improved ladling apparatus which overcomes the above-mentioned disadvantages.
Accordingly, the present invention provides an improved apparatus for permitting the automatic ladling of a molten metal from a bath, which apparatus then transfers the metal to the die casting machine and safely pours same into the machine. The apparatus of the present invention thus overcomes the above-mentioned disadvantages while at the same time it permits a precise quantity of molten metal to be efficiently and safely transferred between a bath and a die casting machine, while additionally permitting this metal to be poured directly into the machine without any appreciable spillage or splashing of the metal. This apparatus also permits the operator to control and stop the automatic operations of the machine while being located at a safe distance from the machine and from the molten metal so as to provide maximum operator safety yet efficient control over the transfer and pouring operations.
Other objects and purposes of the invention will be apparent upon reading the following specification and inspecting the accompanying drawings.